[Some features of measles virus morphogenesis in highly differentiated human astrocyte cultures].

Astrocyte cultures of adult human brain were used to study the morphogenesis of measles virus at different multiplicity of infection. High-dose (1 to 10 TCD50/ml) inoculation of the culture was found to give rise to an acute infection with cytolysis on days 10-12 postinfection and formation of extracellular mature virions. Low multiplicity of infection (0.

[Morphological characteristics of the course of HIV infection in laboratory animals].

The integrative form of infection was obtained in cotton rats intraperitoneally or retrobulbarly infected with the highly-productive strain Zmb HIV-1. Clinically, it appeared as reduced animal weight gain and high mortality rates in the disease terminal stage. The proviral DNA was detected by the polymerase chain reaction in the genomes of cerebral and splenic cells in most animals.

[Virus-induced dyslipidemias as possible risk factors in the development of somatic diseases].

Experimental and clinical studies showed a number of virus infections to be accompanied by lipidemic disorders. Experimentally, dyslipidemias were found in tick-borne encephalitis (TBE) in mice, rotavirus infection in rabbits, and amyotrophic leukospongiosis in guinea pigs. The possibility of correcting the virus-induced lipidemic disorders with an antiviral drug, lincomycin, was demonstrated in TBE in mice.

[Mechanism of accumulation of prion amyloid in the CNS in experimental amyotrophic leukospongiosis].

The mechanism of accumulation of prion amyloid in guinea pig CNS in experimental slow virus disease--amyotrophic leuco-spongiosis (AL) was studied. The complex histochemical, immuno-cytochemical and ultrastructural studies revealed specific amyloid deposits in a few brain capillaries and in most of pia matter vessels. Taking into account the high AL agent titer in spleen throughout the disease period, conclusion was drawn of entering AL agent in CNS through blood-liquor barrier and blood-brain barrier.

[The formation of infectious scrapie-like structures in the persistence of the agent of amyotrophic leukospongiosis in a brain cell culture].

Electron microscopic analysis of specimens from guinea-pig brain cell cultures infected with amyotrophic leucospongiosis agent (belonging to "unconventional" viruses) revealed accumulation in the culture fluid of abnormal filamentous structures similar to scrapie-associated fibrils (SAF) differing in morphology. Most of these SAF-like structures 10-15 nm in diameter contained helically wound protofilaments with a repeat at certain intervals (50-150 nm). When these structures were inoculated into guinea-pig brain astrocyte cultures they produced dystrophic-destructive changes in some (25%) astrocytes, and their intracerebral inoculation to guinea pigs produced an experimental disease.

[The use of electron microscopy for diagnosing spongiform encephalopathies].

The authors suggest an unsophisticated approach to laboratory diagnosis of spongiform encephalopathies induced by unconventional prion viruses, consisting in electron microscopic detection of abnormal helical Scrapie-associated fibrils. These fibrils are detectable in human and animal brain tissue samples and in cell cultures.

[The persistence of the causative agent of amyotrophic leukospongiosis and the astrocyte reaction in monolayer cultures of brain cells].

The amyotrophic leukospongiosis (AL) agent which is considered to be an unconventional virus was shown to replicate and amplify in non-neuronal monolayer brain cell cultures. The AL agent persistence was accompanied by complicated morphofunctional changes in astrocytes, some of them developing a specific cytodystrophic process. Phagocytosis in the infected astrocytes came to its end.

[The biological properties of the HIV isolated from a virus carrier living in the Byelorussian SSR].

Biological properties of an AIDS agent first isolated from a native citizen in the USSR are presented. The source of the virus was a young Byelorussian woman who in the near past had had sexual contacts with a citizen from one of the Central Africa countries. The isolate is thought to be of HIV-I type.

[Electron microscopic study of Lassa virus].

Ultrafiltration through hollow fibrous filters followed by purification in interrupted and linear urografin gradients yielded a Lassa virus suspension of high concentration. The use of gamma-irradiation for inactivation of the frozen virus suspension (-70 degrees C) caused no apparent structural changes of virions and made it possible to examine Lassa virus in electron microscope by negative staining. The observed virus particles in their morphology and sizes did not differ from previously described particles of other members of the Arenaviridae family.